Electronics Anti Rust for car

[Nigel Goodwin]

You've never owned a Vauxhall then

I've owned three as it happens

 

[Hero999]

does anyone know what component it is "910" written in that circuitry.

What circuit?

I think you've got the wrong thread.
https://www.electro-tech-online.com/threads/what-component-is-that.85819/

 

[MrAl]

They use a sacrificial anode - have a look at

Sacrificial anode - Wikipedia, the free encyclopedia

Bit inconvenient having to drive your car in the ocean though?.

Hi Nigel,

Yeah ya know, i was trying to figure out how the heck this works
with a car (i know it works with a ship) because the car is not
surrounded by water.
The articles say that it doesnt matter, but i need some sort of
proof.

I havent even found a decent drawing of a test installation so
i can do some experiments myself.

 

[dknguyen]

You can't get rust without moisture or an electrolyte (a path for ions to travel after electrons have been exchanged). So you don't need an ocean, just moisture. Sacrifical anodes work because only the two most reactive substances present will react since the most postive substance will try and pull electrons from the other substances. But as it pulls the electrons from every other more negative substance, these materials will in turn pull electrons from the most negative substance to replace their own electrons meaning only the most negative substance will lose electrons.

It's like a schoolyard. THe strongest (most positive) bully (atoms or nucleus or element) takes (attracts) money (electrons) from weaker (less postive/more negative) kids (atoms). BUt these kids take money from everyone else to replace their own money. So in the end, only the weakest (most negative) kid (atom) ends up with less money because there is no one weaker for him to bully money out of. So the net result is that the biggest bulley is really stealing money from the weakest kid (the most postiive element is only reacting with the most negative). And of course, we know when two elements exchange electrons we get chemical reactions (rust).

 

[Andy1845c]

So, if this does work in theory, to protect a car, do you suppose you would need small anodes every few inches ( or possibly even closer) to have any effect? I can't imagine a single anode would protect any more then the space very close to it in open moist air. And maybe in more conductive salt water you could space them slightly farther apart?

 

[zeebra]

I've seen some installation, and the "ANODE" is GLUE with epoxy just 1mm from the car surface. Meaning there is no direct contact to the car body. This need to be done properly to orevent direct short-circuit.

 

[Shiftless22]

anti corrosion

I know Chrysler products in late 90's had an option to have a system installed by the dealer. It works, i guess, but once corrosion starts it seems to accelerate rapidly. My 1995 Jeep has it and it had no rust until 2006 (Upstate NY, too!) Maybe find a system and remove it from a used car? Mine has a 2"x2"x3/4" box attached to the front inner fender under the hood with a wire going to the battery. I've heard there may be 2 or 3 of these boxes on the vehicle.
Also, sacrificial anodes...I know an ambulance manufacturer who uses a sacrificial anode mounted between the frame rails to dissipate galvanic reaction between the aluminum box body and the steel/stainless body hardware. Its a block of zinc alloy, about the size of a car battery.

 

[Civil ERTW]

Anode Material

All you really need to do is attach about 4-6 pieces of metal to the bottom of your car. Say 6”X1”X1/4” in size just an example. Basically you just want enough material there so it does not corrode right away and will last for a while. You could use an odd shaped chunk of metal if you wanted but the important point is !!! It must make contact with the steel on the car not just the paint but a good electrical contact !!! Bolt it right to the car anywhere that is convenient. It can be inside or outside the vehicle it does not matter.

Now my chemistry is a little rusty as I haven’t used it for about 8 years but I know that Zinc and aluminum will work as sacrificial anodes. I do not recommend aluminum though as it is just too easy to oxidize it won’t last more than a year. If you live in Canada or anywhere else where they throw salt on the road it won’t last the winter.

If you look in your local phone book or do an online search you will be able to find a metal supplier near you who will be able to sell you some zinc bars. Zinc is not really a common material used so you may have to phone a few places before you find it. Get the Zinc, some bolts and you are away to the races. You don’t need to build any electric circuits unless you really want to.

Cheers!

 

[Leftyretro]

Hello,


No, this is a definite working idea. Rusting occurs due to oxidation which
is caused by electrons.
Big apps include huge steel ships, which use electronics now to control rust
better than ever before, much better than having to repaint cyclically.

Doesn't sound like it would work for an auto because there has to be a ionic conductive path from the two metals in addition to their direct contact. From the Wikipedia article:

"It is important to understand that for this mode of corrosion protection to function there must be simultaneously present an electron pathway between the anode and the metal to be protected (e.g.,a wire or direct contact) and an ion pathway between the anode and the metal to be protected (e.g., water or moist soil) to form a closed circuit; thus simply bolting a piece of active metal such as zinc to a less- active metal, such as mild steel, in air will not furnish any protection."

Lefty

 

[Civil ERTW]

Basic High School Chemistry

Don’t believe most of what you read on Wiki as it is inaccurate and vague at best and outright wrong at worst.

There must be an electrical contact between the anode and the steel car body this is true. The second part is however misleading. It is true that this will now work in completely dry air with 0% humidity. But if your car is in dry air with 0% humidity you don’t need to worry because it JUST WON’T RUST. The moisture in the air is the medium which will cause the reaction to take place and if the reaction takes place then the sacrificial anode will protect your car.

Do not read Wikipedia. This is just basic high school electrochemistry and any grade 12 high school student taking chemistry can tell you the same.
I've studied chemistry at the university level and I can tell you this does in fact work. But the best advice I can give anyone is: don't belive anything you are told without verifying it first. So please don’t take my word for it, go out to a library and pick up a text book on general chemistry and do some “real” research.